Utility knife



May 25, 193 7.

D. FRlSOLl UTILITY KNIFE Filed Sept. 29, 1956 INVDENTOR; J0me nzqo Jnwola ATTORNEY.

Fatented May 25, 1937 @NETEB hi'ATE PATENT @FFEQE UTILITY KNIFE Domenico Frisoli, Newark, N. J.

Application September 29, 1936, Serial No. 103,108

1 Claim.

This invention relates to cutting devices and more particularly refers to improvements in knives of the type having a removable blade. The advent of the safety razor has made it possible to secure razor blades at very low cost and it also has given rise to a practically inexhaustible supply of used blades which can be had for the asking and which while no longer usable for shaving purposes still retain an edge sharp enough to make them serviceable for many other purposes.

As a consequence, a number of arrangements have been proposed whereby safety razor blades can be removably inserted in suitably designed holders in order to produce cutting implements of various characters such as knives, scrapers, flower cutters, etc.

In the case of certain types of knives thus produced, chiefly intended for trimming paper or cutting off clippings or drawings and for similar purposes where the knife is used not by cutting the material with its edge as a whole but by running the outer end of its edge along the line of cutting, the rectangular shape of the blade causes its forward edge to intercept proper vision and thus interferes with the performance of the work.

This is especially due to the fact that the blade is inserted in a holder and the thickness of the holder is considerably greater than that of the blade, so that when the holder is seen from above the blade itself is entirely out of sight.

Furthermore, in performing the work of cutting clippings, drawings, etc., the knife is generally held at a distance from the body of the user, so that the line of vision from the eye to the cutting edge is not vertical but inclined and the back of the holder remains directly in its way.

The primary object of this invention is to provide in a device of the character specified, a novel and improved type of blade whereby cutting and trimming operations will be facilitated.

Another object is to provide a novel and improved type of holder for safety razor blades adapted to form therewith a utility knife, said holder being so designed that a blade can be instantly inserted therein or removed therefrom and yet will be firmly held when inserted in position.

A further object is to provide in a device of the character specified, a novel and improved type of holder for safety razor blades adapted to be inexpensively produced out of a single piece of sheet metal, said holder being designed so as to conveniently fit the hand and being adapted to firmly hold a blade by frictional pressure without requiring the use of any screws or other 5 fastening means.

Other objects and advantages of the present invention will more fully appear as the description proceeds and will be set forth and claimed in the appended claim. 10

My invention is illustrated by way of example in the accompanying drawing, in which:

Fig. 1 is a plan view of my improved utility knife with the blade attached;

Fig. 2 is a side view in elevation thereof; 15

Fig. 3 is a side view in elevation of the blade detached;

Fig. 4 is an end view thereof;

Fig. 5 is a cross sectional view of the holder and blade in an enlarged scale through line 55 of Fig. 2; and

Fig. 6 is a cross sectional view of the handle portion of the holder in an enlarged scale through line G5 of Fig. 2.

In the preferred embodiment of my invention, the front end of the cutting edge of the blade is forwardly spaced with respect to the front end of its mounting edge, so that the front part of the blade is slanted from front to rear at an angle considerably less than 90, the resulting inclination of the front edge of the blade corresponding more or less to the normal inclination of the line of vision from the eye to the point of cutting when the device is in use.

Thus, referri g to the drawing, 10 designates 35 a blade provided, like a safety razor blade of the usual type, with a mounting edge shield ll. Instead of having a rectangular outline, the blade has rearwardly inclined front and rear edges l2, l3, so that the front end 14 of holding shield II will remain rearwardly spaced with respect to the front end l5 of the cutting edge.

As a result it will be seen that if dot and dash line a-a in Figs. 2 and 3 is taken to represent the line of vision from the eye to the cutting point, there is no obstruction in said line of vision and a clear View of the work as it proceeds can be had.

It is obvious that for the purpose mentioned it is not necessary that the rear edge l3 of the blade be directed at a slant like the front edge, in fact if the blade is obtained by grinding a safety razor blade of the usual type so as to produce the desired pointed front end the rear edge can be left at right angles to the cutting edge if desired.

In actual practice, however, it is preferable to have the blades made up directly from new stock in the desired outline so that since the blades are cut one after the other from a steel strip by severing the material at the required angle the resulting pieces will have both the front and rear edge at a slant as shown in the drawing.

The device also includes a special holder in which the blade can be removably inserted. Said holder shown at 16 consists of a sheet metal blank bent along. its central longitudinal line to form a front clamping portion l1 and a handle portion l8 rearwardly extending therefrom.

The front clamping portion is in the form of two jaws I9, 20 laterally spaced so" as to form a longitudinal passage open at the front end, said passage being adapted to receive the mounting edge shield of the blade inserted endwise therethrough.

It is to be understood that said shield will fit snugly within said passage, the jaws I9, 28 pressing lightly against said shield enough to frictionally retain it in position while allowing it to be withdrawn by hand without too much difficulty.

The length of the clamping portion I1 is such that the front end of the blade mounting shield will register with or remain outwardly spaced a short distance from the front end of the clamping portion I! when the blade is inserted in position.

At the rear of the passage within the clamping portion the two sides of the handle portion are brought to abut against each other and are preferably reinforced by a longitudinally extending outwardly bulging embossed rib 2 I.

Besides reinforcing the structure ribs 2| serve to give body to the handle so that it can be conveniently gripped by hand of the user and firmly held. In order to further improve the gripping qualities of the handle, I prefer to make it with a stream-lined contour, that is, thinning down from the front towards the rear as shown in Fig. 2, said contour further serving to greatly improve the appearance of the device.

At its tip end, the handle can be provided with a hole 22 for fastening and suspending the device within convenient reach of the user. The holder can be inexpensively produced out of sheet metal of a suitable gauge and has proved very effective for the purpose for which it is intended and is easy to hold and operate.

Minor constructional details of my invention may vary to a certain extent from those shown without departing from the inventive idea. The

drawing should therefore be understood as being intended for illustrative purposes only and not in a limiting sense.

Accordingly, I reserve the right to carry my invention into practice in all those ways and manners which may enter, fairly, into the scope of the appended claim.

I claim:

A cutting implement. of the character described, comprising a blade having a cutting edge, a mounting edge provided with a flat longitudinal guard element and parallel front and rear edges rearwardly inclined with respect to said cutting edge and a holder for said blade consisting of a single sheet metal blank bent along its central longitudinal line, to form a front clamping portion having a section adapted to register with and snugly receive the guard element of said blade when said guard element is inserted endwise therethrough, and a handle rearwardly extending from said clamping portion, said handle having a streamlined section from front to rear and having its sides embossed to form a longitudinally extending outwardly bulging body therefor.

DOMENICO FRISOLI. 

